The invention relates to a cartilage replacement implant for the biological regeneration of a damaged cartilage area of articular cartilage in the human body, comprising a cell carrier which has a defect-contacting surface for placement on the damaged cartilage area and is formed and designed for colonization with human cells.
The invention further relates to a method for producing a cartilage replacement implant for the biological regeneration of damaged articular cartilage in the human body, wherein a cell carrier is used, which has a defect-contacting surface for placement on the damaged cartilage area and is formed and designed for colonization with human cells.
Cartilage replacement implants of the kind described at the outset are used without or after previous inoculation with the body's own cells for the reconstruction of cartilage defects in articular cartilage in the human body. Biomaterials which can be resorbed by the body are usually selected.
However, with biomaterials for a cell-free implantation with or without growth factors or in the carrier-coupled transplantation of cells, for example, chondrocytes obtained and proliferated from the body's own cells or mesenchymal stem cells, into a tissue defect, for example, a damaged cartilage area, there is the problem that in the course of their resorption, the biomaterials used develop the tendency to contract. Such a contraction and hence shrinkage of biomaterials can often be observed after their contact with cells both in vitro and in vivo and is caused, above all, by contractile elements of seeded or immigrated cells. An undesired consequence of this is that upon commencement of resorption of the biomaterials, the mechanical stability of the implant structures diminishes and the contraction caused by the cells results in a considerable change in shape and volume contraction of the biomaterial.
In the biological regeneration of different tissues of the locomotor system and, in particular, in the reconstruction of structures under pressure load, for example, the articular cartilage in the knee, the annulus fibrosus of the intervertebral disc or the nucleus pulposus of the intervertebral disc, it is, however, of great importance that, as far as possible, a gap-free fusion should take place between the regenerated material resulting from the replacement implant and the healthy surrounding structures of the recipient site, i.e., of the defective tissue area. Gap formations between the regenerated material and healthy surrounding structures of the recipient site, or, in other words, the failure of implant and recipient structures to grow together in a stable manner, may, however, endanger the functional results of the biological reconstruction in the course of further developments. For example, a gap formation in the area of transition between local cartilage and replacement implant at cartilage level constitutes a biomechanical weak point and often forms the starting point of further cartilage degeneration.
The object underlying the present invention is, therefore, to so improve a cartilage replacement implant and a method for producing a cartilage replacement implant that gap formation is minimized between adjacent contact surfaces of the implant and surrounding recipient tissue after implantation of the cartilage replacement implant.